The present invention relates to automotive key interlock safety assemblies and, in particular, to a parking brake actuated assembly for preventing the ignition from releasing the ignition key without first setting the parking brake.
Manual transmission automobiles have long suffered from the potential threat of vehicle runaway, where upon stopping the vehicle, the operator has failed to engage the parking brake or place the vehicle into a forward or reverse gear. The present invention is, accordingly, directed to alleviating this problem for the majority of possible runaway circumstances, short of the operator leaving the ignition keys in the ignition. Additionally, the present invention in its various embodiments is adapative to the most typically encountered ignition key configurations; that is, a dash-mounted cylinder/disc assembly and a column-mounted cylinder/slide bar assembly.
Prior to the present invention, a number of ignition key interlocked assemblies have been developed for variously preventing the unintentional locking of an automobile's doors, without first removing the keys; locking the shift column or steering shaft upon removing the key; and turning off the headlights, before removing the key. Example of patents related to such devices can be found upon reference to U.S. Pat. Nos. 2,105,350; 3,708,032; 3,765,262; 3,654,600; 4,232,538; and 4,154,992.
While the above patents relate to key interlocked assemblies, they do not address the problem of preventing inadvertent vehicle runaway or rolling, upon leaving the vehicle. Two attempts at solving this problem, however, can be found upon reference to U.S. Nos. 2,218,730 and 3,917,021. Of these patents, the '730 patent is directed to an ignition assembly having a related manually actuated locking lever such that the drive shaft and rear wheels of a vehicle are locked, upon removing the key from the ignition. Alternatively, the '021 patent relates to a column ignition assembly wherein the key may not be removed until the automatic transmission is placed in park and the key is placed in the "lock" position. However, a rather elaborate, belt-driven assembly is required to perform these functions and which in any case is not convenient for the standard transmission vehicle. It is to be noted, too, that for some makes of modern standard transmission cars, attempts have also been made in the present inventions's direction by making it is necessary to place the vehicle in a specific gear (e.g. reverse) before the key can be removed. However, such assemblies fall short of requiring the operator to additionally set the parking brake and which is generally the more positive safety mechanism, should the clutch be worn.
Accordingly, it is a primary object of the present invention to require that the emergency brake be set, before the key can be released from the ignition. In order to accomplish this function, a spring-loaded lever and latch assembly are coupled to the switch block so that the lever will always be spring loaded, to engage a mating notch, and prevent the iginition from being returned to the key "release" position thereby restraining the key, if and when the parking brake is unset. Only upon engaging the parking brake, will the key release. In one embodiment of the present invention, an assembly of this type is coupled to a dash-mounted key cylinder; and in another embodiment, the assembly is coupled to a column-mounted, lever actuated lock assembly. Also, while the preferred embodiments contemplate simple cable assembly, still other embodiments, contemplate a solenoid actuated assemblies; and all embodiments further contemplate a visual and audible operator warning system.
The above objects, advantages and distinctions of the present invention as well as others, will, however, become more apparent upon referring to the following description of the present invention with respect to the following drawings. Before referring thereto, though, it is to be recognized that the present invention is described principally with respect to its presently preferred embodiment and, accordingly, various modifications may be made thereto by those of skill in the art, without the departing from the spirit and scope of the present invention.